Torque converter



March 20, 1951 ERNST 2,546,062

TORQUE CONVERTER Filed Dec. 28, 1945 4 Sheets-Sheet 1 INVENTOR. Hen/5 EBA/5 7' BY mzpmm umy fli'TOE/VEYS H. ERNST TORQUE CONVERTER March 20, 1951 4 Sheets$heet 2 Filed Dec. 2a, 1945 '50 INVENTOR.

HFINS EBA 5 7' MKMW 5 W R O T A March 20, 1951 ERNST 2,546,062

TORQUE CONVERTER Filed Dec. 28, 1945 I 4-Sh98t$sh88t 5 1 WW l IN VEN TOR.

HHNS EBA 5 7" ATTORNEYS v March 0, 1951 H. ERNST 2,546,062

' :roR qE CONVERTER 4 Sheets-Sheet 4 Filed Dec. 28, 1945 I INVENTOR. 6% HH/VS tie/v57 Patented Mar. 20, 1951 UNITED STATES PATENT OFFICE 16 Claims.

This invention relates to improvements in machine tool drives and is practicularly related to a novel and improved form ofdrive mechanism for a milling machine cutter spindle.

In machine tools of this type the cutter spindle is customarily driven directly by a change speed gear transmission actuated by a suitable constant speed prime mover or motor. When this direct gear drive is utilized to rotate the cutter spindle certain disadvantages are encountered due to the fact that a milling cutter on the spindle is formed with a plurality of cutting teeth which intermittentl engage the work piece during the cutting operation. This intermittent cutting action between work and tool results in an irregular transmission of power through the drive gearing due to the tendency of the spindle to jump ahead between cuts and the momentary retardance as a new tooth operatively engages the work.

The irregular non-uniform rotation of the cutter spindle relative to the uniform rotation of the prime mover is due to the necessary deflections and clearances between the various dliVillg elements in the change gear transmission with the result that at certain feeds and speeds considerable vibration or' chatter is produced in the driving mechanism and undue strain exerted on the power transmitting gears. Also, this intermittent action tends to produce objectionable noise during the operation of the machine and also makes it difficult to produce accurately finished work surfaces.

It is, therefore, one of the objects of this invention to provide a machine tool spindle drive embodying a vibration dampener which will minimize th vibration of intermittent engagement between cutter and work being transmitted in a positive manner to the gear transmission to thus avoid setting up recurrent strain, chattering, and the like in the transmission mechanism.

A further object of this invention is the provision of an improved self-contained hydraulic shock absorber mechanism for use in power transmissions.

Another object is to provide a vibration dampening or yielding hydraulic coupling mechanism for regulating the drive connection between the driving and driven members of a power transmission system.

A further object is to provide a hydraulic slip coupling for a power transmission which automatically varies the rate of slip between the driving and driven elements of the transmission in response to variations in the speed of rotation of the coupling.

Other objects and advantage of the present invention should be readily apparent by reference to the following specification, considered in conjunction with the accompanying drawings forming a part thereof and it is to be understood that any modifications may be made in the exact structural details there shown and described, within the scope of the appended claims, without departing from or exceeding the spirit of the invention.

Throughout the several views of the drawings similar reference characters are employed to denote the same or similar parts:

Figure 1 is a diagrammatic section of a milling machine spindle driving transmission incorporating the features of this invention.

Figure 2 is an enlarged transverse section through the vibration dampener or hydraulic coupling indicated on the line 22 in Figure 1.

Figure 3 is a face view of the actuating cam of the coupling indicated b the. line 3-3 in Figure 1.

Figure 4 is a section on the line 4-4 of Figure 3.

Figure 5 is a fragmentary view indicated by the line 5-5 in Figure 2.

Figure 6 is a diagrammatic view of the hydraulic coupling on the line 6-6 of Figure 2.

Figure 7 is an enlarged fragmentary section on the line 1-! of Figure 2.

Figure 8 is a diagram of the hydraulic operating and control circuit for the coupling.

As illustrative of an application to which this invention is particularly adapted, there is shown a milling machine spindle drive, Figure 1, comprising a frame 20 in which is journaled the cutter spindle 2! in appropriate bearings 22 and 23. The cutter spindle is driven by means of a prime mover or electric motor 24 which has a motor pulley 25 over which operates the belts 26 to drive the pulley 2'! fixed on a shaft 28 suitably journaled in appropriate bearings 29 carried in the housing 20. The shaft 28 is arranged to have a change or pick-off gear 39 demountably fastened to its end 28a which drives a mating change or pickoff gear 3| demountably carried on the end 32a of the shaft 32 journaled on appropriate bearings 33 carried in the housing 20. An elongated gear 34 is formed on the shaft 32 and is arranged in constant driving relationship with the gear 35 of a compound gear 36. This compound gear isaxially slidable on a shaft 31 carried in suitable bearings 38 in the housing 20 so as to engage the gear 35 selectively with a gear 39 formed on the compound gear 40 journaled on suitable bearings 4| mounted against axial movement on the cutter spindle 2!. A second gear 42 formed on the compound gear 36 is adapted to be engaged with the gear 43 formed on the compound gear 40 when shifted axially on a shaft 3! in the opposite direction from that when engaging the gear 35 with the gear 39.

In this arrangement there is provided a series of speed changes which may be obtained by the proper selection of pickoif gears 30 -3! and by appropriately shifting the compound gear 35 for either engagement of its gear 35 with the gear 33 for higher speed rotation of the cutter spindle or by engagement of the gear 43 with the gear 42 of the compound gear 40 for slower rotation of the spindle. In this way, a constant speed motor 24 may be utilized and it is also preferable to provide reversible mechanism for the motor 24 for obtaining either direction of rotation for the cutter spindle 2 I.

The compound gear 4llis connected to drive the cutter spindle through a hydraulic coupling comprising a main body portion 44 which is connected to positively drive the cutter spindle 2| through a suitable key 45,'Figure 6, and rigidly held on the tapered portion 2 la of the spindle by the clamping nut 47. Also rigidly fixed to the body portion 44 is the annular piston plunger carrying member 48 around which is also rigidly fixed the outer enclosure ring 49 so that in effect the members 44, 48, and 49 comprise an integral body portion or runner Z of the coupling which rotates positively with the cutter spindle 2!.

In the annular member 48 of the hydraulic coupling body is provided a series of cylinder bores 50 in which are mounted a series of piston plungers In the outer ends of each of these plungers is provided a roller 52 which engages the undulated cam surface 53 of the driving cam or impeller 54 for the coupling. This cam is rigidly attached to the compound gear 49 by suitable screws 55. Relative rotation of the gear 45 with respect to the cutter spindle 21 causes the cam surface 53 to reciprocate the various plunger pistons 5| in the bores 50.

The driving power from the compound gear 40 through the fluid coupling to the cutterv spindle 2! is provided by sustained hydrostatic pressure reacting against the piston plungers'5l as they are mechanically actuated by the cam 54. The source of fluid pressurefor this system is provided by 'a hydraulic pump 56, Figure 8, which receives fluid from reservoir 51 through the suction line 58 and transmits the fluid under pressure to the line 59 which has a branch line Gila connected to a pressure relief valve 5| having a discharge line Bid for return of fluid back-to the reservoir 5? so as to maintain a desired predetermined operating pressure in the line 59.

The pressure supply line 59 from the pump is connected to an oil conductor ring 60, Figures 6 and 8, which is journaled on a suitable bearing surface 62a provided on the member 44 of the coupling Z. An annular groove forming a fluid passageway 62 is provided in the surface 62a in such a way as to be constantly supplied withfiuid pressure from the line 59 during rotation of the cutter spindle 2i. Passageways 63 and 64 formed in the member 44 of the coupling are connected to the respective check valves 55 and 6B which allow free flow of fluid from passageway 63 to the'passageway 67 and from the passageway 64 to the passageway 68 while preventing flow in the opposite direction between the passageways. The passageways El and 68 extend radially outwardly and communicate respectively with the annular 4, grooves 69 and 10 formed in the member 44 of the coupling. A pair of radially disposed ports H and 12 for each of the cylinder bores 55 are formed in the member 48 of the coupling and are connected with the respective annular grooves 55 and I0. Annular grooves 13 formed in each of the plungers 5| are arranged to be alternately connected with the ports H orwiththe ports 12 upon reciprocation of the plungers by. the cam 54. The groove 13 is at all times in communication with the ports 19 which are connected through the passageways and 8|, Figure 5, to the pressure" chambers 50a behind each piston plunger. Each -plunger'thus serves as the valve control means for another 'valve plunger 90 out of phase with operatingplunger, which is two plungers away, to alternately connect the corresponding pressure ch ambertothe ports H or 12 as the plungers are reciprocated by the undulated surfaces 53 of the cam 54""during relative rotation of the gear 40 and the coupling Z.

A pair of radially disposed slip control valves S are provided to interconnect the passageways 69 and 10. Each of these valves has a plunger 82 movable radially, ofthe axis of rotation of the coupling Z in a'bore 83 formed in the member 44. The plungers are-normally urged radially inwardly by compression springs 841 Inward movement of the plungers tends to close 01f ports 85 from ports 86 which are respectively connected through passageways 69a andlfia with the passageways 69 and H3. Outward movement of the plungers tends to open ports 85to allow a restricted flow throughthe valves S between the passageways 69 and vH1.

With the compound gear 40'rotating to drive the coupling and cutter'spindle, as'for instance, in the direction indicated by the arrow X, Figure 8, the cam 54 actuates the plungers so that they function as a pump, permitting fluid 'to enter from passageway 16 under'pressure'from pump 56, through port'l2, and discharging fluid out through port 1|, passageway B9,'passage'way 69a, through the slip control valves S, when open, and the passageway 10a back to .the passageway 10. Rotation of the gear 40 inthe opposite direction as indicated by the arrow Y in Figure 8, will reverse the flow in the passagewaysBS and-Wand the slip control valves S, the operation of the coupling being otherwise the same for either direction of rotation imparted to it by the motor 24;

A predetermined minimum fluid pressure is at all times maintained in the passageways 59 and T0 and the associatedports 1| and lzby the pump 56 which supplies fluid through the check valves 65 .and 66, the relief valve 6i maintaining thedesired pressure. This fluid pressure supply circuit from pump. 56 serves to charge the cylinder'chambers 56a during their connection with the supply grooves 10, thus maintaining the plungers with the rollers 52' in proper operative contact with the u'ndulated surface 53 of the cam 54. This supply'of fluid also compensates for any leakage from the operating circuit associated with the piston plungers.

The cam 54 is so arranged-that upon its rotation relative to the member 48 of the coupling, diametrically oppositely located piston plungers, such as the plungers A, Figures 2 and 8,- are actuated simultaneously to the same positions in their reciprocating cycles. With the cam 54 rotatingin the direction X relative to the coupling and cutter spindle, the plungers A (Figure 8) will begin their downward stroke under pressure from 5. the fluid supplied through the ports '12 connected to the plungers C by riding down on the cam surfaces 53a, Figure 8, passing through the various stages indicated byrthe plungers B, C, D, and E. During this time the corresponding valve controlling plungers C, D, E, F, and G are so positioned as to connect the cylinder chambers 59a of the plungers A to E, inclusive to the ports 12 to allow fluid pressure from the-pump 56 to pass through the check valve 65 and the passageway 10 to charge the chambers 50a with fluid preparatory to the beginning of the compression stroke. As the plungers arrive at the stage indicated by plungersE the suction stroke has been completed and the corresponding valve control plungers G have cut off communication of the chambers 590. with the ports 12.

Continued rotation of the cam 54 relative to the coupling causes the plungers to ride up on the surfaces 53b of the cam in compression stroke through stages E, F, G, and H back to the stage indicated by plungers A to complete their reciprocating cycle. During this compression stroke the corresponding valve control plungers G, H, A, and B are so positioned as to connect the chambers 59a to ports H so that fluid is thus forced out into the passageway 69 from which it is conveyed through the Slip control valves S back to the passageway 19 for return of fluid to the piston plungers. It will be apparent that upon rotation of the cam 54 in the opposite direction Y the same mode of operation of the plungers will take place except that the fluid will be circulated in the opposite direction through the passageways 69 and 19 and the'slip control valves S, fluid being supplied from pump 56 to the circuit through the check valve 66 at this time.

Were it not for the restriction to flow between the passageways 69 and 19 imposed by the slip control valves S the cam 54 would freely rotate relative to the coupling member 48 merely actuating the plungers to circulate fluid between the passageways 69 and 10. However, when the plungers 92 of the valve S are in the position shown in Figure 8 they restrict flow at the ports 85 and pressure will build up in the chambers 59a behind the piston plungers operating in compression stroke to thus restrict the free movement of the piston plungers by the cam 54. For instance, with the valve plunger 82 set to completely block the ports 85 the piston plungers in compression stroke would be hydraulically locked against movement with the result the cam 54 will then drive the coupling and cutter spindle at the same speed at which it is rotating. By conventional change of design of the valve plungers 82 or use of end stops, now shown, it is obvious the position of the valve plungers 82 relative to the ports 85 the flow between the passageways 69 and 19 may be so regulated prior to automatic adjustment as to provide any desired slip between the cam 54 and the coupling and cutter spindle as the transmission is being driven by the motor 24.

The valve plungers 82* of the slip control valves S are arranged to be automatically regulated in accordance with the speed of rotation of the coupling. The radial positioning of the valve plungers 82 renders them responsive to the rate of rotation of the coupling so that increased speed of coupling rotation causes the plungers to move radially outwardly compressing the springs 84 and opening the ports -85. Decreased speed of rotation will cause the springs 84 to move the plungers 82 radially inwardly to close off the ports 85. Thus in this arrangement increased cutter spindle speeds automatically increase the slip through the coupling while decreased spindle speeds automatically decrease the slip through the coupling. The slip control valves S automatically adjust themselves to the speed selected for the cutter spindle by the change gears 30-3! and the shifting of the compound gear 36 so as to provide the desired slip in the coupling C for the speed selected.

Preferably the coupling is controlled by the valves S so as to provide a maximum slip of about two percent when operated at the highest speed and with substantially no slip when operating at the lowest speed in order to maintain the proper torque output to the cutter spindle through the entire speed range of the transmission. The fluid in the chambers 59a behind the piston plungers 5i serves as a yieldable cushion between the transmission and the cutter spindle as it escapes through the slip control valves S, to absorb any vibration or disturbing intermittent forces which would otherwise be intercomm-unicated between the transmission and coupling.

In order to dissipate heat developed in the coupling resulting from compression of the fluid in the chambers 59a and the passage of the fluid through the valves S, an arrangement is provided to continuously circulate a small quantity of fluid from the pump 59 through the coupling passageways 99 or iii, and back to the chambers 59a. Connecting with the annular grooves 69 and F9 in the member 44, at a point removed from the passageways 6'! and 98 supplying these grooves, are the ports 3'! and 88, Figures 2, '7, and 8, which communicate with the bore 89 in which is slidably carried the shuttle valve plunger 99. This plunger is adapted to be actuated by fluid pressure from the passageways 69 and "i9. Passageway 99 is connected through passageways 9i and 92 to the pressure chamber 93 behind one end of the plunger 99 while passageway 10 is connected through passageways 94 and 95 to the pressure chamber 99 behind the other end of the plunger.

With the coupling rotating, for example, in the direction X so as to create a higher pressure in passageway 69 than in passageway T9 due to restriction to flow between these passageways by v the slip control valves 3 as explained, pressure from the passageways 69 applied in the pressure chamber 93 will be greater than the pressure applied in the chamber 95 from the passageway '49. The plunger 99 will thus be moved to the position shown in Figures '7 and 8 to connect port 88 through the annular groove 9? of the plunger to the exhaust port 98 in which is provided a fixed fluid resistance 99 from which fluid discharges and returns by suitable means to the reservoir 5?, the port 8? at this time being blocked by the plunger. permit a continuous predetermined escape of fluid from the passageway 19 which is made up by the supply from the pump 56 entering the passageway 19 through the check valve 56 while maintaining the minimum pressure in the cir cuit established by the relief valve 6 i. When the coupling is rotating in the opposite direction Y the pressure will then be higher in the passageway 79 with the result the plunger 99 will be shifted to connect passageway 69 to the resistance 99 while blocking ofl passageway '19 at the port 88, the pump 56 then supplying fluid through the check valve 65 to make up that discharged through the resistance 99. In this way fluid is continuously circulated through the coupling by The resistance 99 is proportioned to egsaegoee tween said impeller and said pump, and a fluid resistance serially connected in said circuit to restrict flower fluid therein to cause said impeller to yieldingly drive said runner comprising a pair of control valves in said runner element, control plungers in said valves disposed for movement radially of the axis of rotation of said impeller, and resilient means to normally urge said plungers toward the axis of rotation of said runner element so that the radial position of said plungers is determined by the rate of rotation of said runner to control the slip in said coupling.

2. In a power transmission for conveying power from a prime mover to a member to be driven, a hydraulic coupling comprising an impellerdriven by said-prime mover and a runner connected to the member to be driven, a fluid pressure pump in said runner having a series of piston plungers, an actuating cam on said impeller for sequentially actuating said plungers in pumping action, a seriesof pressure chambers behind said plungers, intake and exhaust ports associated with each of said plungers, and valve means in said plungers for alternately connecting one or the other of said ports to said chambers, a closed fluid pressure circuit between said intake and exhaust ports for circulation of fluid therebetween upon reciprocation of said plungers by said cam, fluid resistance means in said circuit to restrict the circulation of fluid therein to cause a yielding driving action between said impeller and said runner, and a source of fluid pressure connected to said intake ports to maintain a supply of fluid pressure in said circuit.

3. In a power transmission coupling, impeller and runner members, a fluid pressure pumping device in one of said members, a mechanical driving connection between the other of said members and said pump operative to actuate said pump by the relative movement of said impeller and runner members, a closed fluid pressure circuit connected to said pumping means, a variable fiuid resistance in said circuit to oppose the driving of said pump by said impeller, and means for automatically varying said fluid resistance in response" to speed variations in said coupling so as to change the relative slip between said impeller and said runner, a source of fluid pressure connected to said circuit to maintain a predetermined minimum pressure therein, and a restricted fluid discharge opening in said pumping device to discharge a predetermined volume of fluid continuously from said pump to dissipate heat generated in the fluid in said closed circuit.

4. In a fluid pressure power transmission, a hydrostatic slip coupling comprising a driving member, a driven member, a fluid pressure pump in one of said members, mechanical driving means interconnecting said pump and the other of said members, a'closed fluid pressure circuit connected to the intake and exhaust ports of said pump, valve control means in said pump effective to reverse the intake and exhaust ports thereof upon change in direction of relative rotat-ion of "said unvmgam "driven member's, a slip control valve means serially connected in said closed circuit adapted to restrict flow theieiii' to cause said driving 'element to yieldiiigly rotate saiddriven member, 'a' source of fluid pressure, andfluid pressure control means "for 'autoniati callyfcon'necting said "source of fluid pressure to the intake ports of said'p'umpihg' means 'for either direction of relative rotati'ohof said-members;

55 In" 'a-fluid pressure power transmission, a hydrostatic slip coupling comprising a driving mem her, a-- drivenmember; 'a flu'id pressure pump in one of sa'idmembers} mechanical driving means interconnectingsaid pump andthe other of said members, a closed-fluid" pressure ci'rcuit connected to the intake and exhaust ports of said-pump, valve control means in said'pumpeflectiveto i'everse the intake and exhaust portstherof upbn change indirection of relative rotation of' said driving and driven members; a su controi valve means serially connected in said "closed circuit adapted to restrict flow therein to cause said driving element to yieldingly-rotate said driven member, a source of fluid pressure, fluid pressure control means for automatically connecting said source of fluid pressure to the intake ports-of said pumping means for "either direction of relative rotation of said members, and further fluid pressure control means operable by the-difference in pressure at the intakeand exhaust port's oi said fluid flow therein comprising -radiallydisposed plungers yield-inglyurged inwardly or the axisof rotation of said driven' member" and movable radially outwardlyin' response to the rate of rota said circuit interconnectingsaid intake and ex hau'st' ports may be increased withincrease of speed of rotation 'of said coupling and decreased with decrease of speed of rotation of said coupling, and mechanical actuating means for 'said plungers operated'by' said driven member'to operate'said pistons'to circulate fluid in said'circuit whil 'yie-ldingly restricting relative rotation of said driving and driven members.

7. Ina"power"transmission coupling, impeller and runner members-a fluid pressure pumping device in oneof said-members, a"mechanical driving connection between-"the other of said members and said pump operative to actuate said pump. by the irelati've' movementof said impeller and runner" members a closed fluid pressure circuit"c0nnected to said pump, means for determining the rate offluid transference through the circuitincludinga plurality of-radially shiftable centrifugally operable resistance means interposed m thcirciiit', valve meansestablish-ing compression and-expansion areas in the closed circuit and an auxiliary pressur supply circuit coupled with the closed fluid pressure circuit at opposite sides of the resistance 9 means for maintaining a prescribed pressure within the expansion areas of the system in either direction of relative movement of the impeller and runner members.

8. In a power transmission coupling, impeller and runner members, a fluid pressure pumping device in one of said members, a mechanical driving connection between the other of said members and said pump operativeto actuate said pump by the relative movement of said impeller and runner members, a closed fluid pressure circuit connected to said pump, means for determining the rate of fluid transference through the circuit including a plurality of radially shiftable centrifugally operable resistance means interposed in the circuit, an auxiliary pressure supply circuit coupled with the closed fluid pressure circuit at opposite sides of the resistancemeans for maintaining a prescribed pressure Within the system, the resistance means providing a high pressure side and a low pressure side within the closed circuit, a bleeder conduit, and control means actuable by the pressure in the high pressure side for coupling the low pressure side of the circuit to said bleeder.

9. A hydraulic mechanism of the character described, including reversably operable pumping means and a transferring conduit system including a pair of conduit members interchangeably effective as high or low pressure conduits, a resistance means in the transferring circuit for determining the relative pressures of the conduits in one direction or the other of operation of the pumping means, means for continuously supplying fluid under pressure to the circuit, and means for effecting a limited discharge of fluid from the low pressure side of the circuit irrespective of the direction of operation of the pumping means, said means including a shuttle valve, means coupling opposite terminii of the shuttle valve with the pressure conduits whereby the position of the valve will be determined by the pressure in the high pressure conduit, an exhaust connection, and auxiliary discharge ports from the pressure conduits alternatively couplable by the valve to the exhaust connection, said ports being so positioned that in either direction of shifting of the shuttle valve by high pressure in one of the conduits the port of the opposite conduit will be coupled by way of the valve to the exhaust.

10. A multi-cylinder pumping mechanism of the character described, includin a pump body having a multiplicity of closed end pump cylinders formed therein, plungers slidable in the cylinders having terminal piston portions and intermediate valve groove portions, a first series of 10 having a multiplicity of closed end pump cylin ders formed therein, plungers slidable in the cyl-- inders having terminal piston portions and intermediate valve groove portions, a first series of fluid conduits extending from the terminal portions of the several cylinders to intermediate por-' tions of remote cylinders in the pump body, a pair of additional conduits coupled with each cylinder in spanning relation to the connection of the cylinder conduit therewith whereby on reciprocation of the pump plunger of an individual cylinder, said conduits will be alternately coupled by the valve portion thereof with the end conduit of a remote cylinder, means for main-- taining a basic pressure in the pair of conduits, additional meansefiective during operation of the pump for effecting a difierential in pressure between said conduits whereby pressure is built up in one of said hydraulic conduits by successive actuation of the plungers toward the closed ends of the cylinders, an undulating cam simul-- taneously en aging all of said plungers for confluid conduits extending from the terminal porsure between said conduits whereby pressure is built up in one of said hydraulic conduits by successive actuation of the plungers towardthe closed ends of the cylinders.

11. A multi-cylinder pumping mechanism of the character described, including a pump body trolling the position thereof, the contour of the cam being such as to effect difierential positioning of hydraulically connected pairs of plungers, and means for efiecting cont nuous relative rotary movement of the cam and pump body for efiecting successive.corresponding movements of the plungers. 1

12. In a machine tool or the like. the combination with a power source and a driven member, of a yieldable coupling intervening said parts, said coupling including a runner carried by the dr ven member. said r nner h ving a circumferential series of axially extending bores formed therein, said bores being clo ed at one end, a series of plungers each lidably mounted in one of the bores, the plun ers nro ectin beyond the bores, an undulating cam actuable by the power source and dis osed, for multaneous engagement with the project ng portions of all the plungers. a hydraulic conduit extending 'from the closed end of each bore to an intermediate portion of a remotely situated bore, eachof said plungers having an annular groove of width to,

remain in communication with the conduit connection to the intermediate port on-of the 'bore at all points in the stroke of said plunger, a first h draulic pres ure line cou led with all of the bores at a point intermediate each individual bore conduit and the end of the bore, a second hydraulic pressure line cou led with all of the bores at a more remote point, whereby during recinrocatien the grooves of the plungers will alter atel cou le the respective bore terminal conduits w th one or the other of said hydraulic pressure ines, and r e ns for maintaining a pressure condition n both aid first and econd series of p s ure lines wherebv there w ll he a hydraulic reactio urg ng the several plun ers into en a ement with the cam irrespective of the plun er efiected cond it counl n s thereof;

13. In a machine tool or the like. the combination with a po er source and a driven member, of a yieldable coupling intervening said. parts, said coupling including a runner carried by the driven member, said runner having a circum-1 ferential seriesof axiallyextending bores formed. therein, said bores being closed at one end, a

series of plungers each slidably mounted in one of the bores, the plungers projecting beyond the bores, an undulating cam actuable by the power source and disposed for simultaneous engage-' ment with the projecting portions of all the plungers, a hydraulic conduit extending from the 111 closed end ofeachbore to an intermediate portion ofza -remotely situated bore; each of said plungers having an annular groove of width to remainin communication with the conduit connection to the intermediate portion of the bore atall points in the stroke of said plunger, a first hydraulic pressure line coupled with all of the bores at a pointintermediate each individual bOr-e-;.conduit and the end of the bore, a second hydraulic. pressure line. coupled with all of the bores .ata. more'remote point, whereby during reciprocation the grooves of the plungers. will alternately couple the respective bore terminal condui-ts with one or the other of said hydraulic pressure lines-means formaintaining a pressurecondition in both said first and second series of pressure lines, and resistance meansainterconnecting the first and second hydraulic pressure lineswhereby on relative rotation of the cam and-runner ahigh pressure. condition will be createdtin .one of the lines by the compression-action-of. the successive plungers.

.14. ,In a machine tool or the like, the combination with a power sourceand a .driven member, of ,a'yieldable coupling intervening said parts, said coupling, including a runner carried by the driven..member, said runner having a circumferential series ofaxially extending bores formed therein, said bores being closed at one end, a series of "plungerseach slidably mounted inone of the bores; the .plungers projecting beyond the bores, an undulating cameactuable by the power sourceand disposed for simultaneous engage ment with ,the projecting portions of all the plunger-sahydraulic conduit extending from the closed .end. of'each vbore to an intermediate portiongof -.a remotelysituated bore, each of said plungers havingan annular groove of width to remain-in communication with the conduit connection to the. intermediate portion of the bore atall points in the strokeof said plunger, a first hydraulic pressure line coupled withall of the bores at .a-pointintermediate each individual bore: conduit. and-the end of-the bore a second hydraulic pressure, linev coupled with all of the bores at'a-more: remote point, whereby during reciprocation. the grooves of the plungers will alternately couplethe respective bore terminal conduits, with one or the other of said hydraulic pressure lines, meansfor maintaining a pressure condition in both said first and-second" series of pressure lines; and-variable resistance means interconnecting the first and second hydraulic ressure .lines whereby on relative rotation of the camandrunnena high pressure condition will be. -cr.eated in. one of the lines by the compression action cf the successive plung rs.

..l5...ln.a\machine tool Or the like, the combination with;a..power= source and adriven member,.of,.a, yielda'ble coupling intervening said par-ts, said coupling including a runner-carried by the driven-.membcnsaid.runner having a circumferential series; of axially extending bores formed ther.ein,..said boresbeing .closed at one end, a seriesotplungers eachslidabl mounted in one oi-the bores, the ,plungersprojecting beyond the bores, an undulatingcamactuable .by the power sourceanddisnosed for, simultaneous en eme with the,projectingportions of all the plungers,

a. hydraulic conduitrextending from the closed end of eachboretoan intermediate portion of a, remotely situated bore, each of said plungers having any annular groove of, width to remain in communicationwith the conduitconnection to the intermediate portion of the bore. at all points; in thestroke of said plunger, a first hydraulic :pressure line coupled with all of'the bores at-a point intermediate each individual bore conduit and the .end of the bore, a second hydraulic pressure line coupled with all of the-bores at a-rmo re remote point, whereby duringreciprocation the grooves of. the plungers will; alternately'couple the respective bore terminal conduits with one orthe other of said .hydraulic pressure lines, means for maintaining aqpressure condition in both said first and second series io i'pressure lines, resistance 7 means interconnecting the; first and second hydraulic pressure lines wherebyonrelative -rotation of theca-m and runner: ahigh pressure condition. will be createdin one of; the lines by the .compressiomaction of the successive plungers, and means for automaticallyeifecting an exhaustbleedingirom thelower pressure. line.

16. In a machine.- tool or thelike,; the combination with a power sourceand-a driven member, of a yieldable coupling intervening said parts, said coupling including a runner carried by the driven member, said runner having-a circumferential series of: axially extending: bores formed therein, said bores. being closed at one end, a series of plungers each slidably'mountediin one of the bores, thewplungers projecting beyond the bores, an undulating camactuable bythe power source and disposed for simultaneous engagement with the projecting portions of all of the plungers, a hydraulic gconduit extending from the closed end;Of5 e3Ch" bore to; effect an out of phase continu u var abl posit nin t e of,

spaced plungers having a substantially: out of phase relationship, a hydraulic conduit extending from the'closed end'of each bore to an intermediate portion of a spaced bore whose plunger is in substantially 90- out of phase relationship with the'plunger of the connected bore, each of said plungers having an annular groove of width to remain incommunication with the conduit connection to the intermediate I portion of theboreat allpoints in the stroke of said plunger; a first hydraulic pressure line coupled with all of the bores at a point. intermediate each individual bore conduit and theend of the bore, a second hydraulic pressure line coupled with all of the-bores ata more-remote point, whereby during reciprocation the grooves of the plungers will alternately couple the respective bore terminal conduits with one or the other of said hydraulic pressure lines, and means for maintaining a pressure condition inboth said first and second series of pressure lines whereby there will be a hydraulic reaction urging the several'plungers into engagement with the cam irrespective of the plunger effected conduit couplings thereof.

HANS. ERNST.

, REFERENCES .CHTED.

The following. references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,245,412 Wheeler Nov. 6, 1917 2,025,472 Perry Dec. 24, 1935 2,050,836 Graham Aug. 11, 1936 2,173,856 Orshansky Sept. 26, 1939 2,408,574 Morris, Oct, 1, 1946 

